Cable tie strap fasteners are well known. They usually consist of a one-piece cable strap of flexible plastic material which comprises a toothed central region and at one end of which there is provided a socket, for engagement by the free end tip of the strap once the strap is looped onto itself. This socket includes a strap push-in channel member and a locking pawl extending transversely of this channel member and destined to releasably lockingly engage the tooth gaps of the strap. Examples of such prior art fasteners are described in the following patents:
(a) Canadian patent Nos. 951094 to Panduit Corp. (U.S.A.); No. 1015535 to USM Corp. (U.S.A.); No. 1073640 to ITW-ATECO G.m.b.H. (West Germany); and No. 1177625 to Emhart Industries inc. (U.S.A.); (b) U.S. Pat. No. 3,542,321 to Minnesota Mining and Manufacturing Co. (U.S.A.); 3,731,347 to Panduit Corp. (U.S.A.); 3,900,923 to Steven Manufacturing Co. (U.S.A.); No. 3,973,292 to Robert Yves Gabriel Bonnet (France); No. 3,991,444 and 4,191,334 both to Panduit Corp. (U.S.A.); No. 4,236,280 to Courtesy Mold and Tool Corp. (U.S.A.); No. 4,490,886 to Nifco, inc. (Japan); and No. 4,805,856 to Panduit Corp. (issued in Feb. 1989).
In most of the known cable straps, the axis of the strap in the region of the transition to the socket extends usually substantially perpendicular to the strap push-in direction. On the other hand, in e.g. Canadian patent No. 1073640, the push-in channel is arranged parallel to the direction of the strap, so that in the region of the entry of the push-through opening, the strap is led back parallel to itself; as can be seen from FIG. 1 of this latter patent, this means that the total useful diameter of the thereby formed strap loop is less than it could be, since some losses are incurred at the strap tip inlet of the socket (13). The same problem occurs in Canadian patent No. 1015535.